1. Field of the Invention
The present invention relates to a control technique for reducing electric power wasted for projection in a mobile projector apparatus having a projector function.
2. Description of the Background Art
Conventionally, some of portable, small-sized, and light-weight mobile terminals 101 represented by mobile phones and the like have a function of projecting a picture, as shown in FIG. 7. Specifically, mobile terminal 101 includes a projecting unit 102 and a projection key 103. Projecting unit 102 is disposed at a lower portion of mobile terminal 101 to modulate light from a light source and project a picture. Projection key 103 is disposed on an outer wall surface of mobile terminal 101 to switch on/off the projection of the picture from projecting unit 102 each time when it is pressed down.
With the configuration described above, a picture 105 having a size larger than a display size displayed on a display panel 104 such as a liquid crystal monitor of mobile terminal 101 can be projected from projecting unit 102, and a plurality of people can simultaneously confirm the picture.
However, since the amount of light of a light source in a small-sized mobile terminal is smaller than that of an ordinary projector, when a user accidentally turns on the light source in a bright place such as in the daytime, the user may put the mobile terminal into his/her pocket or bag with the light source illuminated, without noticing it. This results in a waste of a battery.